Question

Help ı need to solv thıs worksheet

Answer 1

130, - 12, 56.1, 11.2

these are all arithmetic sequences with n th term formula

`a_(n)` =
`a_(1)` + (n - 1 )d

where d is the common difference and
`a_(1)` the first term

(1)

d = 10 - 4 = 4 - (- 2 ) = 6 and
`a_(1)` = - 14

`a_(25)` = - 14 + (24 × 6) = - 14 + 144 = 130

(2)

d = 14 - 16 = 16 - 18 = - 2 and
`a_(1)` = 22

`a_(18)` = 22 + (17 × - 2 ) = 22 - 34 = - 12

(3)

`a_(50)` = 2.2 + (49 × 1.1) = 2.2 + 53.9 = 56.1

(4)

`a_(12)` = - 4.2 + (11 × 1.4 ) = - 4.2 + 15.4 = 11.2